Refractor Shootout

[MalcolmM]

I was hoping to put my 60mm up against Armagh Observatory's mighty 10" Grubb refractor. It's a beautiful instrument, over 100 years old, driven by a clockwork drive, and was used in the compilation of the New General Catalogue of Nebulae and Clusters of Stars in 1888 by John Dreyer, the then director of Armagh Observatory.

Unfortunately, despite waiting for over two hours, the clouds defeated us and the shootout did not happen! Part of me was secretly glad, as this scope has the reputation of being an exquisite visual instrument, putting up spell binding views, though apparently the Grubb is quite nice too 🙂

Much as I love my little Tak, I think the 140 year old Grubb would have left it for dust!

Malcolm 

[Mr Spock]

I'd love a scope like that. What a thing of beauty. I can't find any technical details for it. Is it f15?

[MalcolmM]

14 minutes ago, Mr Spock said:

I'd love a scope like that. What a thing of beauty. I can't find any technical details for it. Is it f15?

There's not that much about it online. I'll see if I can find out any more information. I'll also bring a tape measure up and get you the focal length!

Malcolm 

[Ags]

I had no idea your 60 mm Tak was so big! Do you have any pictures of the Grubb?

[maw lod qan]

Wow!

[M40]

Superb, you have to admire the Victorians. I was fortunate enough to be able to visit the Norman Lockyer Observatory in Sidmouth on a sunny day earlier in the year and they have three similar telescopes, one of which was a diy jobby that Norman Lockyer made himself and with which he discovered and named Helium. Here is his diy jobby, not sure if I could get that stuff from B&Q today 

[Mr H in Yorkshire]

53 minutes ago, M40 said:

not sure if I could get that stuff from B&Q today 

I reckon my local agricultural merchants have everything, maybe not the kinder egg though.

Edited December 17, 2023 by Mr H in Yorkshire

[M40]

That's not an egg, it's a critical balancing mechanism that only the Victorians could build

[Louis D]

Seriously Steampunk looking.  I love it!

I'm picturing the astronomers of the day like this:

[globular]

Aren't all the domes fantastic!

[Peter Drew]

A refurb looks overdue!      🙂

[The60mmKid]

Now this is a cool shootout. Common' little Tak! You've got fluorite!

[MalcolmM]

1 hour ago, globular said:

Aren't all the domes fantastic!

Rope and pully operated dome rotation. No electronics in sight. It really is fabulous!

Malcolm 

[Padraic M]

That's a beautiful of piece of Victorian engineering art. I wouldn't like to have to tweak the polar alignment though!

[badhex]

On 17/12/2023 at 00:23, MalcolmM said:

I was hoping to put my 60mm up against Armagh Observatory's mighty 10" Grubb refractor. It's a beautiful instrument, over 100 years old, driven by a clockwork drive, and was used in the compilation of the New General Catalogue of Nebulae and Clusters of Stars in 1888 by John Dreyer, the then director of Armagh Observatory.

Unfortunately, despite waiting for over two hours, the clouds defeated us and the shootout did not happen! Part of me was secretly glad, as this scope has the reputation of being an exquisite visual instrument, putting up spell binding views, though apparently the Grubb is quite nice too 🙂

Much as I love my little Tak, I think the 140 year old Grubb would have left it for dust!

Malcolm 

Amazing looking scope. The blue and brass is an awesome colour scheme! Quite awe I spring that it was used in compiling the New General Catalogue as well! 

[ollypenrice]

University of Central Lancs has a Grubb Parsons like this. (Actually it has two in parallel, one corrected for visual, one for plate photography. I observed Saturn through it once. This was not a very informative target but the image was decent, though not as good as that of a 12 inch SCT, I don't think. That's not really the point, though... 

Olly

[Peter Drew]

I've used three large Grubb refractors, the UCL 15", the Stonyhurst 15" and the 8" at UMIST.  I have to say I was a little disappointed with the performance though their condition at the time might have been partly responsible.  I offered to clean the UCL 15" but "red tape" got in the way, I had permission to clean the Stonyhurst 15" but considering most of the problem was between the lenses and the condition of the cell was such that I was reluctant to dismantle it.  We repaired a few components and at least got the telescope operating again.  I did remove the cell from the UMIST 8", dismantled the objective and cleaned and reset the components.  Little improvement but the location in central Manchester doesn't help, my 8.5" refractor refigured by Es Reid is better.  The 8" Cooke refractors at UCL (London) and Moor Park Preston are superb.       🙂

[fireballxl5]

14 minutes ago, Peter Drew said:

The 8" Cooke refractors at UCL (London) and Moor Park Preston are superb.

The 8" at Moor Park has been out of action now for 20 years, mainly owing to deterioration of the observatory's general building infrastructure (now refurbished). With just the dome electricals and some minor mechanicals sort (wip), hopefully the scope will be usable soon,  in the new year perhaps.

[MalcolmM]

Very interesting notes on actually observing through Grubb telescopes @ollypenrice and @Peter Drew. Hopefully I'll get a chance to observe with this one, it's used often over the winter. I was chatting with an ex staff member who had first used it 70 years ago and he said it was a lovely scope to use, easy to manoeuvre and put up stunning views, particularly of the planets. The original objective was apparently replaced, it was so good it was decided  it should be used for optical research or something. Apparently it was an optician rather than an astronomer that made that decision! I'm hoping to try and find out a bit more about its history. 

Malcolm 

[MalcolmM]

On 17/12/2023 at 08:47, Mr Spock said:

I'd love a scope like that. What a thing of beauty. I can't find any technical details for it. Is it f15?

Spot on @Mr Spock, f15.

Malcolm